1. Field of the Invention
In general, the present invention relates to an apparatus, system and method of providing a tank base and or pedestal for oil and gas operations. More particularly, the present invention provides a polyethylene plastic tank base system sized to provide a load-bearing support for an aboveground storage tank and is generally non-corrosive, chemical resistant, tolerant to temperature variations and non-absorbing.
2. Description of the Prior Art
Tanks and tank batteries are essential elements in oil and gas production. In the oil and gas industry, the term “battery” generally refers to a group of containers called “tanks” that are a grouping of interconnected metal storage tanks situated to receive the output of one or more wells for crude oil production and or a producing lease. A tank battery is also called a battery. Typically, in the tank battery, the oil volume is measured and tested before pumping the oil into the pipeline system and the group of tanks at a well site is used to store oil prior to sale to a pipeline company. A typical tank battery contains one or more tanks and usually has a capacity equal to four days production.
It is desirable to raise a tank and or tank battery off the ground. Due to the nature of the use of these tanks, it is not unusual for the bottom of the tank to be situated where water, chemicals, corrosive elements, and liquids in general are present and can accumulate at the base of the tank. Because these tanks are made from metal and exposed to highly corrosive elements, these tanks are prone to rusting and deteriorating, which is obviously undesirable and potentially a safety risk as well as an environmental risk.
Tanks are typically raised to minimize contact with fluids thus reducing and or preventing corrosion as well as allowing for proper hook up of pipes and fittings. Furthermore, a majority of tanks have a manhole at the bottom of the tank that is bolted on. This hole will need to be accessed at various points throughout the tanks life for cleaning, plumbing and repair work. If that manhole is at ground level it cannot easily be removed.
The prior art for providing a base is generally one of two methods. The first is generally providing a metal ring with a larger diameter than the tank and filling it with pea gravel before setting the tank in place on top of the pea gravel and the second is generally providing a dense foam ring with a larger diameter than the tank and placing the tank on the foam base.
The metal ring construction typically utilizes a grade band metal bolted together to form a base greater than the diameter of the containment tank it supports. The diameter of the support structure may be a base of poured pea gravel to form a 3″ to 8″ base inside the ring. This allows the tank to be at a level greater than the ground level and aids in the slow deterioration of the tank due to any standing fluid within the secondary tank area, whether the fluid is natural such as rainwater or accidental spills or leaks. The pea gravel currently used is naturally porous and allows for the absorption for any number of contaminants such as oil, salts, acids, and so forth that come into contact with the gravel, causing permanent contamination, which still tends to spill out of the gravel upon oversaturation. Attempts to treat or wash out the contaminants are costly, difficult, and to-date, ineffective.
The process of constructing the traditional metal tank rings takes numerous steps, time and money. First the galvanized strips of metal are bolted together on the location by dozens of small nuts and bolts forming a circle. The ring is then set in the approximate position and the first bucket of chat or pea gravel is placed into the center of the ring, once the gravel is spread towards the edges of the ring a tape measure is used to check the diameter and ensure it is perfect. The ring is repeatedly measured and then adjusted by kicking or slamming into the metal edge in order to achieve the perfect circle. Once set, more buckets of pea gravel are added by the tractor and a leveling screed is used to smooth the top of the pea gravel forming a flat surface that the tank can set on.
There are many negatives associated with these prior art devices such as, this process can take a five man crew approximately 30 minutes per ring in labor cost and requires a tractor. Furthermore, once set, it is difficult to adjust and impossible to move without starting over. Also, the pea gravel must be hauled by a heavy hauler to the location causing extra expense and environmental impact. Still further, pea gravel and chat are also highly corrosive to the bottom of a steel tank. Another negative to a galvanized tank ring is that once the pea gravel enters a containment that is lined with a plastic liner, the pea gravel can cause damage to the liner by being pushed or rubbed through. Still further, water is held or trapped by the pea gravel or chat and this mixture is also corrosive to the bottom of the tank. Many in the industry have banned pea gravel inside the containment for the above reasons.
The other generally known prior art method is utilization of a dense foam pedestal that is cut into circular patterns to fit the bottom of a tank. The foam is then coated with poly-urea and ultimately the tank is placed on top. There are also known negative features of this method such as the generally delicate and easily punctured nature of the material. Once punctured, the foam can take on liquid, loose density and fail. Furthermore, these foam pedestals are hard to haul and transport because of their size and generally being a one-piece construction. The one-piece construction also makes them prone to be blown around and damaged by strong winds during the installation process. It is also common for these types of devices to be torn during transportation in general as well as moved off the desired location with relatively small winds.
It is obviously desirable to provide a base and or pedestal in oil and gas operations in general and more specifically tank battery operations. The balance of cost, time, and operational efficiency has created a need for a new and improved tank base and or pedestal system and method. Thus, there is a need for an apparatus, method and system that provides a support structure and reduces liquid accumulation around a tank and or tank battery. The current invention provides an inexpensive, time saving, more reliable apparatus, system and method where the prior art fails.